Marine macroalgae waste: A potential feedstock for biogas production

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Pardilhó, S (Author) FEUP; Rui Boaventura (Author) FEUP; Manuel Fonseca Almeida (Author) FEUP; Joana Dias (Author) FEUP

Journal

Title: Journal of Environmental Management

Vol. 304

ISSN: 0301-4797

Publisher: Elsevier

Indexing

ISI Web of Knowledge

ISI Web of Science

Scopus - 0 Citations

Other information

Authenticus ID: P-00V-XHX

DOI: 10.1016/j.jenvman.2021.114309

Abstract (EN): In the present study, marine macroalgae waste, mainly composed by Saccorhiza polyschides, was collected from a beach in northern Portugal and evaluated as feedstock for anaerobic digestion. Batch experiments (500 mL flasks, 300 mL working volume) were conducted at the following conditions: mesophilic temperature (37 °C); 80 rpm stirring speed; 150 mL inoculum (anaerobically digested sludge) and variable total solids content (0.9, 1.7, 2.5 and 3.5% TS). Methane concentration and volume of biogas obtained were monitored during up to 57 days by optical sensors and milligascounters, respectively. The results show that an increase in total solids content up to 2.5% TS led to the highest biogas volume and methane concentration. The maximum biogas yield was 227 ± 4 mL/g VS (2.5% TS, 53 operation days), with the maximum methane content in the biogas being 64.5 ± 0.6% (51 operation days). A maximum methane yield of 146 ± 2 mL/g VS was consequently estimated. At the end of the process (57 days), an average of 43% COD reduction and 46% VS reduction were observed. These results correspond to about 27% of the theoretical maximum methane production. Using 3.5% TS the inhibition of the process was observed, by the decrease in pH, most likely due to the accumulation of volatile fatty acids. The results indicate that marine macroalgae waste may be a good candidate as substrate for anaerobic digestion processes, most probably by co-digestion. © 2021 Elsevier Ltd

Language: English

Type (Professor's evaluation): Scientific